<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html lang="en">
  <head>
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="created" content="2018-10-23T06:18:10.521000000">
    <meta name="changed" content="2018-10-23T06:18:42.262000000">
    <meta http-equiv="content-type" content="text/html; charset=utf-8">
    <meta http-equiv="Content-Language" content="en">
    <title>
      Creating circuits
    </title>
    <link rel="stylesheet" type="text/css" href="../../style.css">
  </head>
  <body>
    <div class="maindiv">
      <h1>
        Creating circuits
      </h1>
      <p>
        Every Logisim project is actually a library of circuits. In its simplest form, each project has only one circuit (called <b class=reffig>main</b> by default), but it is easy to add more: Click on the <img class="icontxt" src="../../../../img-guide/projadd.png" alt="#########" height=16 width=16> of the <a href="../gui/gui-toolsbar.html#tb4">small menu bar</a> above the navigation panel or <b class="tkeybd">right click</b> on the root of the tree in the navigation panel or else select <b class=menu>|&nbsp;Project&nbsp;|</b>→<b class=menu>|&nbsp;Add Circuit...&nbsp;|</b> and then type any name you like for the new circuit you want to create.
      <p>
        <b class=note>Note:</b> The name of the circuits must begin with a letter (A..Z, a..z) it can contain the signs (., _) And numbers.
      </p>
      <p>
        Suppose we want to build a 2-to-1 multiplexer named <b class=reffig>Mux_2to1</b>." After adding the circuit, Logisim will look like this.
      </p>
      <p align="center">
        <img class="notscal" src="../../../img-guide/subcirc-1-add.png" alt="#########">
      </p>
      <p>
        In the explorer pane, you can now see that the project now contains two circuits, <b class=reffig>main</b>, and <b class=reffig>Mux_2to1</b> Logisim draws a magnifying glass over the icon of the circuit currently being viewed; the current circuit name also appears in the window's title bar.
      </p>
      <p>
        After editing the circuit to appear like a <b class=reffig>Mux_2to1</b>, we might end up with the following circuit.
      </p>
      <p align="center">
        <img src="../../../img-guide/subcirc-2-done.png" alt="#########">
      </p>
      <p>
        <b>Next:</b> <a href="sub-using.html">Using subcircuits</a>.
      </p>
    </div>
  </body>
</html>
